Device and method for controlling transmission of vehicle

Abstract

A device and a method of controlling a transmission of a vehicle may include a determining device that compares road information related to a first road section corresponding to a road section on which the vehicle is currently traveling and a second road section disposed ahead of the first road section to determine a gradient of the second road section, a calculating device that determines an increase amount of a gradient-inducing resistance based on a difference between gradients of the first road section and the second road section according to a determination result from the determining device, and a controller that compares the increase amount of the gradient-inducing resistance with a reference value to perform transmission control and engine torque control based on comparison of the increase amount of the gradient-inducing resistance with the reference value.

What is claimed is: 
     
       1. A vehicle transmission control device comprising:
 a determining device configured to compare road information related to a first road section corresponding to a road section on which the vehicle is currently traveling and a second road section disposed ahead of the first road section to determine a gradient of the second road section; 
 a calculating device connected to the determining device and configured to determine an increase amount of a gradient-inducing resistance based on a difference between a gradient of the first road section and the gradient of the second road section; and 
 a controller connected to the determining device and the calculating device and configured to compare the increase amount of the gradient-inducing resistance with a reference value to perform transmission control and engine torque control based on comparison of the increase amount of the gradient-inducing resistance with the reference value. 
 
     
     
       2. The vehicle transmission control device of  claim 1 , wherein the controller is configured to downshift a gear stage and to control an engine torque based on a driving force predicted at a downshifted state upon determining that the increase amount of the gradient-inducing resistance is greater than the reference value. 
     
     
       3. The vehicle transmission control device of  claim 2 , wherein the calculating device is configured to determine each driving force predicted when the gear stage is downshifted one stage by one stage upon determining that the increase amount of the gradient-inducing resistance is greater than the reference value. 
     
     
       4. The vehicle transmission control device of  claim 3 , wherein the controller is configured to:
 determine a gear stage at which the determined driving force is greater than or equal to the increase amount of the gradient-inducing resistance; and 
 determine a gear stage higher than the determined gear stage by one stage as a target gear stage. 
 
     
     
       5. The vehicle transmission control device of  claim 4 , wherein the calculating device is configured to determine a first engine torque increase amount based on an engine torque in the first road section, an engine torque in the second road section, and an engine torque increase amount when downshifting to the target gear stage upon determining that the gear stage is shifted to the target gear stage. 
     
     
       6. The vehicle transmission control device of  claim 5 , wherein the controller is configured to control an engine torque output based on a sum of an engine torque output value in the first road section and the first engine torque increase amount. 
     
     
       7. The vehicle transmission control device of  claim 1 , wherein the reference value is defined as a driving force predicted when a current gear stage is downshifted by one stage. 
     
     
       8. The vehicle transmission control device of  claim 1 , wherein the controller is configured to perform the engine torque control based on a current gear stage when the increase amount of the gradient-inducing resistance is equal to or lower than the reference value. 
     
     
       9. The vehicle transmission control device of  claim 8 , wherein the determining device is configured to determine a second engine torque increase amount based on a difference between an engine torque in the first road section and an engine torque in the second road section. 
     
     
       10. The vehicle transmission control device of  claim 9 , wherein the controller is configured to control an engine torque output based on a sum of an engine torque output value in the first road section and the second engine torque increase amount. 
     
     
       11. The vehicle transmission control device of  claim 1 , wherein the controller is configured to return to a previous driving control state when the vehicle passes through the second road section. 
     
     
       12. The vehicle transmission control device of  claim 1 , further including:
 a communicator connected to the controller and configured to receive the road information related to a road ahead of the vehicle from a navigation, wherein the information related to the road ahead of the vehicle includes the gradient of the first road section and the gradient of the second road section. 
 
     
     
       13. A method of controlling a transmission of a vehicle, the method comprising:
 comparing road information related to a first road section corresponding to a road section on which the vehicle is currently traveling and a second road section disposed ahead of the first road section to determine a gradient of the second road section; 
 determining an increase amount of a gradient-inducing resistance based on a difference between a gradient of the first road section and the gradient of the second road section; and 
 comparing the increase amount of the gradient-inducing resistance with a reference value to perform transmission control and engine torque control based on comparison of the increase amount of the gradient-inducing resistance with the reference value. 
 
     
     
       14. The method of  claim 13 , further including:
 determining each driving force predicted when a gear stage is downshifted one stage by one stage when the increase amount of the gradient-inducing resistance is greater than the reference value. 
 
     
     
       15. The method of  claim 14 , wherein the performing of the transmission control and the engine torque control includes:
 determining a gear stage at which the determined driving force is greater than or equal to the increase amount of the gradient-inducing resistance; 
 determining a gear stage higher than the determined gear stage by one stage as a target gear stage; and 
 performing a downshifting to the determined target gear stage. 
 
     
     
       16. The method of  claim 15 , wherein the performing of the transmission control and the engine torque control includes:
 determining a first engine torque increase amount based on an engine torque in the first road section, an engine torque in the second road section, and an engine torque increase amount when downshifting to the target gear stage. 
 
     
     
       17. The method of  claim 16 , wherein the performing of the transmission control and the engine torque control further includes:
 controlling an engine torque output based on a sum of an engine torque output value in the first road section and the first engine torque increase amount. 
 
     
     
       18. The method of  claim 13 , further including:
 performing the engine torque control based on a current gear stage when the increase amount of the gradient-inducing resistance is equal to or lower than the reference value. 
 
     
     
       19. The method of  claim 18 , wherein the performing of the engine torque control includes:
 determining a second engine torque increase amount based on a difference between an engine torque in the first road section and an engine torque in the second road section. 
 
     
     
       20. The method of  claim 19 , wherein the performing of the engine torque control includes:
 controlling an engine torque output based on a sum of an engine torque output value in the first road section and the second engine torque increase amount. 
 
     
     
       21. The method of  claim 13 , further including:
 receiving the road information related to the second road section before the determining of the gradient of the second road section.